Anode assembly for cathodic protection



y 1962 R. B. BENDER ANODE ASSEMBLY FOR CATHODIC PROTECTION Filed June15, 1959 RICHARD 8. BE NDE R INVENTOR.

ATTORNEY United States Patent 3,046,213 ANODE ASSEMBLY FOR CATHODICPROTECTION Richard B. Bender, Fort Worth, Tex., assignor to TejasPlastics Materials Supply Company, Fort Worth, Tex.,

a corporation of Texas Filed June 15, 1959, Ser. No. 820,214 1 Claim.(Cl. 204-196) This invention relates to corrosion control, and hasreference to an improved insulating head for supporting an anodehorizontally in a metal container such as an oil storage tank, oilemulsion heater treater, filter tank, or other vessel wherein theinterior of the vessel is subject to corrosion by reason of galvanicaction.

There are two types of cathodic protection systems to 'Which theinvention lends itself. One is the use of an external source of directcurrent which, when impressed on an anode of iron, Durion, aluminum, orgraphite causes current to flow from the anode through the electrolyteto the metal surface to be protected. The other type of system operatesin the same manner, but creates its own electromotive force by reason ofthe presence of different metals in contact with the electrolyticsolution, that is, the metal surface to be protected and the metal anodein the electrolyte. For example, when the surface to be protected issteel, the anode may be magnesium or zinc.

An object of the invention is to provide an improved dielectric head forhorizontally supporting an anode in a vessel for cathodic protection.

Another object is to provide a dielectric head for the described purposewhich will eliminate the possibility of contact between the anode andthe Vessel.

Another object of the invention is to provide a head of the describedclass supported outwardly of the vessel and one which is convenientlyinstalled and secured in place.

A particular object is to provide a dielectric head capable of beingsupported at a point intermediate its ends when horizontally positionedin the side of a vessel.

A further object of the invention is to provide a dielectric head forthe described purpose which eliminates the use of washers, gaskets, orthe like.

These and other objects of the invention will become apparent from thefollowing description and the accompanying drawing wherein:

FIGURE 1 is a side elevation and broken sectional view of an anodeassembly and installation in accordance with the invention.

FIGURE 2 is an end elevation of the invention as viewed from the outsideof the tank where the anode is installed.

FIGURE 3 is a transverse sectional view taken on line 3-3 of FIGURE 1.

The form of the invention shown includes a relatively long, round anodehaving a cylindrical insulating head 11 molded on one end thereof. Thehead 11 is of a suitable t-hermosetting plastic such as polyester orepoxy, and the closed end 12 of which is enlarged and flanged, as at 13,for engagement by a circular clamp 14, hereinafter described. An exampleof a suitable resin is described in Modern Plastics Encyclopaedia,September 1958, published by Breskin Publications, page 103, under theheading A New Epoxy Molding Compound. An electrical contact 15 in theform of a rod extends inwardly through the head 11 and into the anode10. Thus, if the anode 10 is of a type wherein applied current isemployed the contact 15 may extend only a short distance into the anode,but where the anode is of the self-generating type, it is preferred thatthe contact extend substantially into the anode, for example, half wayof the length thereof, or may extend entirely through the anode if soice desired. Preferably, the anode 10 is cast directly on the contact 15and threads 16 on the contact help secure the latter in place. The outerend of the contact 15' is also threaded, as is 17, for receiving nuts 18between which the terminal 19 of an electrical lead 20 is secured.

In the preferred form of the invention, the threads 17 on the extendingend of the contact 15 are threaded outwardly of the head 11 andterminate before reaching the closed end \12 thereof. Integral with theclosed end 12 of the head 11 there is a tubular receiver 21 which ismolded on the corresponding end of the anode 10. Intermediate the endsof the receiver 21 there is a shoulder 22, also of thermosetting resin,for resting on the edge of an opening 23 in the vertical tank wall 25.It is to be understood that in place of the tank wall 25 the opening 23may be in a manway or the like, not shown.

Around the opening 23 there is a short, tubular extension or nipple 26welded as at 24 to the outer surface of the tank 25, and the outer endof which nipple includes a groove 27 for receiving the inner flange 28of the circular clamp 14. Similarly, there is a corresponding outergroove 29 in the flange 13 of the head 11 for receiving the outer flange30 of said clamp. Between the flanges 28 and 30 of the clamp 14, andaround the connection between the head 1 1 and the outer end of thenipple 26, there is an expansible gasket 31. The clamp 14 is comprisedof upper and lower halves 32, as shown in FIGURE 2, and which halves areheld together by bolts 33.

In view of the foregoing description, it will be apparent that the anode10 may be installed in and removed from the tank wall 25 by the simpleexpedient of opening the clamp 14 and inserting or removing the anode10. By reason of the location of the relatively long insulating receiver21, the anode is fully protected from the metal tank wall. Preferably,and as illustrated in FIGURE 1, the shoulder 22 of the receiver 21 is ofa diameter slightly less than the tank wall opening 23; thus, by reasonof the at least slightly flexible construction of the head flange 13,the weight of the anode 10 will cause the shoulder 22 to rest on thelower periphery of the opening 23 in the tank 25.

It will also be apparent from the foregoing that since the closed end112 and receiver 21 of the head 11 are directly molded on the anode, nowashers, spacers or means drawing the head 11 against the anode 10 arerequired.

The invention is not limited to the exemplary construction herein shownand described, but may be made in various ways within the scope of theappended claim.

What is claimed is:

An anode assembly for cathodic protection in a metal vessel wherein aremovable elongate anode is horizontally positioned in a hole in a wallof the vessel and extending inwardly thereof, said assembly comprising:an insulating head of dielectric synthetic resin material mounteddirectly on one end of said anode and including a closed end and ananode receiver of dielectric material integral therewith, said receiverextending through said hole, means tightly receiving one end of saidanode in said receiver, the remaining end extending into said vessel andexposed therein, a nipple on the outer surface of said vessel aroundsaid hole and adapted to receive said receiver and anode, a circularclamp engaging said head on the outer end of said nipple, an electricalcontact extending through the closed end of said head and into saidanode, the diameter of said receiver being sufficiently large enough torest on the bottom of said hole which comprises a support for saidreceiver inwardly of said head.

(References on following page) 3,046,213 3 1 References Cited in thefile of this patent 2,568,594 Robinson Sept. 18, 1951 UNITED STATESPATENTS 2,805,987 ThOIIl 6t 31. Sept. 0, 1957 393,072 Marquand Nov. 20,1888 FOREIGN PATENTS 1,366,257 Gush Jan. 18, 1921 5 250,567 GreatBritain July 1, 1926 2,025,243 Jackson et a1, Dec. 24, 1935

